A three-week-old seal pup was found in a back garden four miles (6.4km) away from the sea.
The RSPCA said it was found in Terrington St Clement in Norfolk.
It said it believed the pup travelled up a drainage system in the hope of finding water or food.
Animal collection officer Naemi Kilbey said she was grateful the "incredibly feisty little fella" was found, otherwise he may have died from starvation.
The seal pup was taken to the RSPCA East Winch Wildlife Centre where it was checked over.
Ms Kilbey said it was found in a garden in an area surrounded by agricultural farmland and "there was definitely no sign of the sea or a beach".
She said the water system had only two inches of water in it "so this poor pup must have just kept trying to travel further and further down in the hope of finding water or food".
"He was an incredibly feisty little fella and it took all my strength to catch and rescue him, but it would have been his spirit and fight for life, that would have kept him alive during his ordeal," she said.
You may also like:
"I'm just so grateful to the homeowner who found him and called us, if the pup hadn't been found he would have likely have died of starvation due to not being able to find any food."
The centre said the pup, which was found on Wednesday, will be monitored and fed before it is released into The Wash.